The Study of Diluted Magnetic Semiconductor: The Case of Manganese Doped Gallium Nitride
Issue:
Volume 7, Issue 1, March 2022
Pages:
1-10
Received:
16 January 2021
Accepted:
21 April 2021
Published:
16 February 2022
Abstract: The diluted magnetic semiconductor, (Ga, Mn) N has recently attracted intense research interest for the purpose of spintronics application. The material is believed to circumvent the difficulty of combining data processing and mass storage facilities in a single crystal besides solving non-volatility problems. The concentration x, of Mn that substitutes for a fraction of Ga in the compound is thought to contribute a large concentration of magnetic moments and holes. The material studied is focused on dilute magnetic semiconductors (DMS) like Ga1-XMnXN that play a key role in semiconductor spintronics. Due to their ferromagnetic properties they can be used in magnetic sensors and as spin injectors. The basic problems for applications are, however, the relatively low Curie temperatures of these systems. Therefore, we focus on the understanding of the magnetic properties and on a reliable calculation of Curie temperatures from first principles. We have developed a theoretical framework for calculating critical temperatures by combining first principles calculations and in terms of the Ruderman–Kittel–Kasuya–Yosida quantum spin model in Green’s function approach. Magnetic properties of the group-III nitride semiconductors are introduced here with basic material parameters (temperature, concentration, heat capacity, etc. Temperature dependencies of the spin wave specific heat, inverse magnetic susceptibility and reduced magnetization are determined. Therefore, the dependence of the Neel temperature on the manganese ion concentration is linear thus for our calculation the highest Neel temperature obtained T=146.3k within the concentration of 0.2.
Abstract: The diluted magnetic semiconductor, (Ga, Mn) N has recently attracted intense research interest for the purpose of spintronics application. The material is believed to circumvent the difficulty of combining data processing and mass storage facilities in a single crystal besides solving non-volatility problems. The concentration x, of Mn that substi...
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Studying the Effect of Delay Time on Intensity of Laser Induced Breakdown Spectroscopy Technique Using Mas Cement Sample
Altaf Alsaid Mohamed Abdalgader,
Abdelmoneim Awadelgied
Issue:
Volume 7, Issue 1, March 2022
Pages:
11-15
Received:
4 February 2022
Accepted:
21 February 2022
Published:
4 March 2022
Abstract: Cement is a soft bond material that hardens and acquires its mechanical properties in the presence of water; it is an industrial product that has many uses, including its use in construction, roads, bridges, and others. It is important in our life to know its components. In this study, a laser-induced breakdown spectrometer was used to detect the elements present in a sample of Sudanese mas cement. In this technique, a high-energy laser is applied to the surface of the sample, ionizing the atoms of the material and then evaporating it, and then producing hot plasma on the surface of the sample, and this plasma is analyzed with a spectrometer, and thus the components of the sample can be known. The laser source used in this study is (Nd: YAG). Delay times are one of the factors affecting the intensity of the libs signal, To determine the relationship between laser delay times and LIBS signal intensity, a mas cement sample was irradiated with 32mj laser pulse energy and (200, 300, 400, 500, 600, 700, 800, 1000, 2000) nanoseconds delay times. We observed a decrease in the LIBS signal with increasing laser delay times. For quantitative analysis, the plasma temperature and electron density at (300, 500 and 700) laser delay times at 32mj laser pulse energy were calculated using standard equations and well-resolved spectral lines for Ca in the region of (422.67, 430.25 and 430.774) nm. It has been observed that when the delay time increases, the plasma temperature decreases and the electron density decrease. It was found that the density of electrons is directly proportional to the temperature of the plasma.
Abstract: Cement is a soft bond material that hardens and acquires its mechanical properties in the presence of water; it is an industrial product that has many uses, including its use in construction, roads, bridges, and others. It is important in our life to know its components. In this study, a laser-induced breakdown spectrometer was used to detect the e...
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